Due to the many complexities, housing planning, especially for vulnerable groups, in a city as large as Tehran, requires a model to simplify the process and speed up calculations, which does not currently exist. With the aim of solving this problem, the present study proposes a model with the following steps: 1) Explaining the objectives 2) Estimating the housing needs of the target community 3) Identifying expandable areas 4) Proposing construction patterns 5) Proposing dispersion patterns 6) Calculations and patterns Financial and 7) suggest operating patterns. The information required to implement the model was collected from two questionnaires and data from the Statistics Center. In this model, three housing models with minimum, optimal and average areas and three types of existing housing construction, 100% infrastructure and freeing up the yard space were used as public urban space. The proposed zoning was adapted to the 22 districts of Tehran Municipality due to compliance with the available data. Sales price and financial calculations were calculated based on the internal rate of return of 20% and contract subsidies, and finally 4 free transfer models, lifelong lease, lease on condition of ownership in the program areas were proposed. The results show that one of the problems in this sector is the lack of appropriate decision-making structure and planning tools that can provide a comprehensive and complete review of the current situation, comprehensive and comprehensive solutions. Therefore, according to the model and using the indicators used, regions 2, 6 and 13 have the lowest and regions 19 and 22 have the highest potential for housing development of low-income and vulnerable groups, and finally, the model has suggested the most housing in regions 22, 4, 19 and 11.

Social sustainability today, as the most important dimension of sustainable development, has an important place in urban planning and its importance in planning is constantly increasing with the increase of social problems and divergence between neighborhoods in terms of performance and participation. Therefore, this requires more research in urban studies. This study was conducted to investigate the role of social participation in the development of social sustainability in neighborhoods. For this purpose, the significance of the significant effect of these two variables has been measured. The research is applied in terms of purpose and descriptive-analytical in terms of method. Data collection was library and field method. The statistical population of the study consists of a group of experts who were selected by the available method of 20 people as the sample size of the study. Data collection tool is a questionnaire based on theoretical foundations and studies conducted on a five-point Likert scale. Data analysis was performed using structural equations with the help of Emus software. The results showed that the social participation of citizens in neighborhoods with a coefficient (beta) of 0.732 has a positive effect on sustainable social development of these neighborhoods and the relationship between these two variables is significant. In other words, sustainable social development will be strengthened by strengthening social participation. And the variables of sense of belonging, satisfaction with the neighborhood, participation in neighborhood activities and trust also have a positive effect on the variables of social participation in neighborhoods.